While there doesn't appear to be any specific legislation in Australia governing a fake COA I would think that the issuing of a fake COA would be considered a dishonest action and therefore fraud. If a complaint of a fake COA was made to an authority then the COA would become an exhibit and therefore a legal document.
Have a look at the article in the below link. I know it is in relation to artwork but there are some very relevant points as to what should be on a 'legit' COA
Why so?, i think you may have misunderstood me, im saying that i would provide a stat dec, stating that the signatures are 100% authentic and that i got them etc
Im put myself in the postion of been sent to gaol if i have lied on a stat dec...